The hydrochlorination of ethylene in the presence of a Friedel-Crafts metal halide catalyst is an old and well-known procedure. The art employs principally ethylene and a substantially high purity hydrogen chloride in a boiling bed reactor. The composition of the boiling bed is substantially the product of the hydrochlorination. Many of the Friedel-Crafts metal halide catalysts have been suggested and depending upon the conversion, temperature of reaction, pressure, etc., the entire scope is employed. Aluminum chloride or ferric chloride, however, are the preferred and most commonly referred-to metal halide Friedel-Crafts catalysts. The principal product of this reaction with ethylene is ethyl chloride. It has become common practice to purify the ethyl chloride from this reaction prior to its use in preparing any number of more highly chlorinated materials. Likewise, the thermochlorination of ethyl chloride is a well-known process. The temperature, pressure, and the ratio of chlorine, with or without catalysts, dictate the product which is obtained. Many processes are known which integrate a di- and trichloro- product such as, for example, chlorinating ethyl chloride to 1,1-dichloroethane recycling the 1,1-dichloroethane with the ethyl chloride feed and producing therefrom 1,1,1-trichloroethane. Several techniques have been disclosed for carrying out such a process. Again in each of these processes, it is normal that the effluent product of the chlorination is separated into the desired product and recycle streams. Some desired product may be recycled as a temperature control, thus a chlorination control medium. The hydrochlorination of unsaturated partially chlorinated hydrocarbons such as vinyl chloride, vinylidene chloride, cis- and trans-dichloroethylene, are each documented in the prior art. The use of ferric chloride and/or aluminum chloride as the metal halide Friedel-Crafts catalyst for these hydrochlorinations is also well known. The separation of each of the products of the hydrochlorination of one or more of the unsaturated partially chlorinated hydrocarbons is a rather lengthy procedure requiring several distillations to obtain high purity products. It is evident from the prior art that the skilled technician approaches the preparation of polychlorinated ethylenes and ethanes in a stepwise manner preferring to separate the intermediate products and purify them before employing them in the next step. This procedure necessitates several large pieces of purification equipment intermediate to the various steps and oftentimes results in compounds being present as impurities in the desired product which create problems in the next step unless removed by chemical means.
It would therefore be advantageous if there were provided a process whereby ethylene and chlorine were the two external reactants introduced into a process and therefrom produce 1,1,1-trichloroethane with a minimum of intermediate separations of reaction products in order to provide feeds for each of the steps of a multi-step process.
It is therefore an object of the present invention to provide such a process.